The aim of this project is to examine how developmental changes in the pragmatic functions and prosody of speech directed to, and produced by, children is affected by children's hearing loss. Prosody is an important cue to the pragmatic function of speech, such as marking questions, statements, requests. Exaggerated prosody is a hallmark of mothers'speech to children. It has higher overall pitch, expanded pitch range, and uses distinctive pitch contours. These features are used to express emotion, guide infants'attention, and facilitate speech perception and language acquisition. Using an NIH-funded database of recordings of mother-child interactions between 4 and 60 months of age (R01DC006681;R01DC004300;P30DC004662), the prevalence of various pragmatic categories of utterances will be assessed to the determine the degree to which mothers speech consists of questions, statements, and other kinds of utterances. These utterances will then be analyzed acoustically to examine how mothers use prosody to express pragmatic function, and how mothers adapt their prosody to their child's age and hearing ability. A parallel acoustical analysis, will examine the pragmatic function of children's speech to their mothers, how children's use of prosody develops and how it is affected by hearing loss. Children's pragmatic and prosodic speech development depends on their early auditory and language experience, which may be limited or affected by hearing loss and their mothers'pragmatic language use. Finally, mother-child interactions will also be analyzed to assess the development of rhythmic coordination in the timing of vocalizations. Coordinated mother-child interaction is important for many developmental outcomes. Understanding how vocal interactions are affected by hearing loss may lead to improved methods of remediation. PUBLIC HEALTH RELEVANCE: This project aims to identify how hearing loss affects the development of the pragmatic and prosodic aspects of vocal interaction between mothers and their children. Using a database of recordings from a longitudinal (4 to 60 months of age) NIH-funded study (R01DC006681;R01DC004300;P30DC04662) of mothers interacting with their normal hearing and hearing impaired children, the pragmatic function of utterances will be coded, and their use of prosody to mark pragmatic functions will be analyzed acoustically. Given previous research demonstrating the importance of quality mother-child interactions on various developmental outcomes in normal hearing children, a greater understanding of the ways in which hearing loss influences these interactions may lead to improved methods of remediation, and speech and language outcomes.